Celiac sprue is a highly prevalent disease in which dietary proteins found in wheat, barley, and rye products known as ‘glutens’ evoke an immune response in the small intestine of genetically predisposed individuals. The resulting inflammation can lead to the degradation of the villi of the small intestine, impeding the absorption of nutrients. Symptoms can appear in early childhood or later in life, and range widely in severity, from diarrhea, fatigue and weight loss to abdominal distension, anemia, and neurological symptoms. There are currently no effective therapies for this lifelong disease except the total elimination of glutens from the diet. Although celiac sprue remains largely underdiagnosed, its' prevalence in the US and Europe is estimated at 0.5-1.0% of the population. The identification of suitable naturally-occurring enzymes as oral therapeutics for celiac disease is difficult due to the stringent physical and chemical requirements to specifically and efficiently degrade gluten-derived peptides in the harsh and highly acidic environment of the human digestive tract.